Portable radio



M Cm3 Smm www June 6 1961 H. H. sTEGLlcH 2,987,616

PORTABLE RADIO Filed DBC. 19, 195'? United States Patent C 2,987,616PORTABLE RADIO Herbert H. Steglich, Wilmette, Ill., assignor to ZenithRadio Corporation, a corporation of Delaware Filed Dec. 19, 1957, Ser.No. 703,877 2 Claims. (Cl. 25il`14) This invention relates in general toportable wave signal receivers and in particular to a telescopic antennaarrangement for use therewith.

Telescopic antennas for use `in portable receivers are well known and,conventionally, are vertically mounted within the receiver cabinet.Telescopic antennas are frequently utilized for reception ofcommunications signals, that is signals outside the standard broadcastband. Since the length of such an antenna is readily adjustable, it canbe accurately tuned for a selected frequency.

However, in order to fully exploit the capabilities of a tunable antennacare must be taken to prevent capacity loading of the antenna whichwould effectively change the electrical length of the antenna and thusdetune it. Capacity loading of an antenna is considerably aggravatedwhen a large conductive mass, eg., a metallic chassis or cabinet isdisposed adjacent the antenna structure. To overcome this loading effectthe operating position of the antenna should be such as to present butan insignificant portion of the antenna surface in juxtaposition withany nearby metallic mass.

A further consideration in regard to portable receivers of the typeherein discussed concerns the cabinet itself. Since plastic, wood, orother non-metallic enclosures do no-t produce significant capacityloading the antenna can be disposed within the cabinet provided it iscarefully oriented with respect to the metal chassis or other metallicmasses within the receiver. A metal cabinet is in many instancespreferable for portable, as well as nonportable, receivers since inaddition to contributing structural rigidity, substantially' completeshielding of the receiver circuitry from external interference iseffected. It is thus apparent, in view of the preceding discussion, thata telescopic antenna conventionally mounted within the receiver would beexceedingly inappropriate for use with metal cabinetry. Furthermore,that portion of an extendable yantenna. which would be enclosed within ametal cabinet would not be available for intercepting radiated signalenergy.

A number of schemes for supporting and concealing extendable antennastructures are Well known and provide for operation of the antennaoutside of the receiver while providing concealed storage when thereceiver is inoperative. Such prior art structures do not admit ofsimplified construction nor, when extended, do they establish theantenna in the most eiiicient operating position.

.It is therefore an object of this invention to provide a telescopicantenna mounting arrangement for a portable radio receiver, whicharrangement substantially precludes antenna loading due to straycapacity effects.

It is also an object of this invention to provide a telescopic antennastructure, for a portable radio, which is fully concealed Whileinoperative but is readily extendable to an operating position.

It is a further object of this invention to provide a telescopic antennastructure for portable receivers which permits utilization of the entireantenna pick-up element.

A portable radio receiver constructed in accordance with this inventioncomprises a cabinet and a conductive chassis contained Within thecabinet which includes a radio receiver circuit. A handle has one endpivotally secured atop the cabinet by a hinge to permit displacement ofthe handle from a rst position in which the handle is substantiallyparallel Ito the adjacent surface of the cabinet to a second position inwhich it is angularly disposed With respect to that surface of thecabinet. A latch mechanism is supported by the cabinet for releasablylocking the handle in the first position. A telescopic rod antenna,normally supported entirely within the handle when the handle isdisposed in the first position, is extensible when the handle isdisplaced to the second posi-tion to `an operating position in which theantenna is angularly and laterally displaced from the chassis to renderthe antenna free from capacitive loading by the chassis. Finally, meansare provided for electrically connecting the antenna to the radioreceiver circuit.

The features of the present invention which are believed to be novel areset forth with panticularity in the appended claims. The organizationand manner of oper ation of the invention, together with further objectsand advantages thereof, may best be understood by reference to thefollowing description taken in connection with the accompanying drawing,in the several figures of which like reference numerals identify likeelements, and in which:

FIGURE l is a front perspective View of a portable radio receiverincorporating the subject invention;

FIGURE 2 is a rear perspective view, partly in section, of a portableradio receiver constructed in accordance with the invention and shown inan operating position;

FIGURE 3 is a fragmentary View, partly in crosssection taken along line3-3 of FIGURE l and showing the handle and antenna construction of thereceiver; and

FIGURE 4 is a fragmentary cross-sectional View illustrating theoperating position of the handle hinge mechanism shown in the upperright hand portion of FIG- URE 3.

The portable radio receiver illustrated in FIGURE 1 is a multi-bandreceiver of the type designed for operation in the Shortwavecommunications bands in addition to the standard broadcast band.Receiver 10 comprises a metal cabinet 11 having :metallic end portions12, 13, a hinged front cover 14 which can be releasably secured by aconventional spring catch 55 and a hinged rear cover 15 (FIGURE 2)likewise having a releasable catch mechanism 56. End section 13 supportsa turret type band selector switch 16 While a tuning knob 17, a tonecontrol 60, and a volume control and switch 61 are mounted on the fron-tof cabinet 11. A ferrite-core loop antenna (not shown) for use inbroadcast band operation is disposed within `a plastic enclosure 18which is supported atop cabinet 11. The end portions 12, 13 of cabinet11 include the respective pedestals 19, 20 which mount a hollowedcarrying handle 21.

FIGURE 2 shows handle 21 angularly disposed with respect to receiver 10and reveals a detachable cover plate 57 secured tohandle 21 byconventional fasteners. A telescopic antenna 22 .having a plastic cap 23is normally supported entirely within hollowed handle 21, and is shownin FIGURE 2 in a partially extended position. The opened extremity ofhandle 21 includes a pair of tabs 24 which facilitate positioning handle21 within pedestal 19 when the antenna is retracted and the handle isrestored to the carrying position. The manner in which handle 21 ispivotally hinged upon pedestal 20 and secured within pedestal 19 is bestillustrated in FIGURES 3 and 4 and will be more fully described below.Electrical means, more specifically conductor 25, connects antenna 22 tothe input section 26 of the radio receiver chassis which includes aradio receiver circuit.

'I'he fragmentary cross-sectional view of handle 21 in FIGURE 3 showstelescopic antenna 22 encased within an antenna base portion 31. Baseportion 31 is mounted in a fiberglass cylinder 28 disposed within handle21. A hinge 29 terminates handle 21 and is fastened thereto. Hinge 29employs a pin 30 which transfixes cylinder 28 and fastens it to thehinge. Pin 30 is rotatably journalled within pedestal 20. Antenna baseportion 31 is axially constrained within cylinder 28 by a screw fastener32 which also electrically connects one end of conductor 25 to baseportion 31 while the posts 33, formed upon the inner surface of hollowhandle 21, provide lateral stability for base 31.

The previously mentioned tabs 24 bear upon a shoulder 3`4 of pedestal 19when handle 21 is in the carrying position as shown. A release latch 35,35 (the primed reference numeral depicting a displaced position of latch35) having a pair of apertured bosses 36 (only one shown) is mountedupon a shaft 37 which is rotatably secured within pedestal 19. A returnspring 38 is mounted upon shaft 37 between bosses 36 and is constrainedbetween an inner surface 39 of pedestal 19 and the inner surface 40 oflatch 35 so as to normally urge release latch 35 against the lip 50 ofend section 12. Latch 35 further includes a shelf 58 at its upperextremity having an aperture 59 which engages a locking post 62 securedto handle 21.

FIGURE 4 shows handle 21 in an angularly displaced upright position andclearly illustrates the detent latch mechanism 41, 41' (the primedreference numeral illustrating a displaced position of detent latch 41)which, like release latch 35, maintains a pair of apertured bosses 42(only one shown) for receiving a mandrel 43 which is rotatablyjournalled within pedestal 20. A detent spring 44 is mounted uponmandrel 43 between bosses 42 and bears against an inner surface 45 ofpedestal 20 and upon a ledge 46 of detent latch 41. The lower extremityof detent latch 41 sustains an offset 47, which bears against the rimportion 48 of end section 13 to restrain latch member 41, and aprojection 65 to facilitate manual actuation of latch 41.

Hinge 29, previously described as terminating handle 21, furtherincludes a land 63 which engages the upper extremity of detent latch 41when the handle 21 is in the carrying position (FIGURE 3) and a footing64 which bears upon latch 41 in a similar manner when the handle isangularly displaced (FIGURE 4).

Operation of receiver is initiated by first displacing front cover 14 toprovide access to controls 17, 60, 61 (FIGURE l). A particular band isthen selected by the tuner selector switch 16 which positions theappropriate terminals of the turret tuner (not shown) for cooperativeengagement with input section 26 of the receiver chassis. Duringreception of wave signals in the broadcast band the loop antennadisposed within enclosure 18 is automatically connected to input section26 and reception is effected in a conventional manner.

Reception of signals in the communications bands is accomplished byfirst positioning selector switch 16 to the desired band. Positioningthe turret tuner for operation in the above-mentioned bands disconnectsthe loop antenna in enclosure 1S and couples telescoping antenna 22 toinput section 26. Antenna 22 is readied for operation by firstdepressing release latch 35 inwardly. As latch 35 pivots about shaft 37,aperture 59 -in shelf 58 is displaced from locking post 62. With latch35 thus depressed handle 21 is angularly displaced from its first orcarrying position to its second or operating position. As hinge 29rotates upon pin 30 about pedestal 20 detent latch 41 is drivencounter-clockwise about mandrel 43 by footing 64 of the hinge.Simultaneously, detent spring 44 is compressed. As handle 21 assumes anupright position (FIGURE 4) the upper extremity of detent latch 41 isdriven beneath footing 64 of hinge 29 through the action of detentspring 44. Handle 21 is thus securely positioned for operation.Telescopic antenna 22 is then withdrawn by clasping cap 23 to initiateextension of antenna 22. The telescoping antenna can be extended to anydesired operating length. Wave signals intercepted by antenna 22 aretranslated to input section 26 via conductor 25.

Handle 21 is re-positioned to its carrying position by rst retractingantenna 22 and then depressing projection 65 on latch 41 inwardly so asto displace latch 41 from beneath footing 64 of hinge 29. Handle 21 isthen rotated downwardly while latch 35 is displaced to enable handle 21to enter pedestal 19. When tabs 24 engage shoulder 34 of pedestal 19latch 35 is released thereby permitting aperture 59 of shelf 58 toengage locking post 62. With handle 21 thus secured receiver 10 can besafely and conveniently transported.

Accordingly, a portable radio receiver 10 as disclosed comprises acabinet 11 containing a chassis which includes a radio receiver circuit.A handle 21 which encloses a telescopic rod antenna 22 is mounted uponthe cabinet and is displaceable from a first or carrying position to asecond or operating position. A conductor 25 is provided forelectrically connecting antenna 22 to the radio receiver circuit. Theoperating position of antenna 22, in which handle 21 is angularlydisplaced, permits utilization of the entire antenna element.Furthermore, by positioning antenna 22 remote from cabinet 11 and itsend sections, undesired antenna loading due to stray capacity effects issubstantially precluded. The combination handle-antenna device hereindisclosed obviates the limitations of prior art antenna arrangementsthrough a simplified and advantageous antenna mounting arrangement.

While a particular embodiment of the invention has been shown anddescribed, it will be obvious to those skilled in the art that changesand modifications may be made without departing from the invention inits broader aspects, and, therefore, the aim in the appended claims isto cover all such changes and modifications as fall within the truespirit and scope of the invention.

I claim:

1. A portable radio receiver comprising: a cabinet; a conductive chassiscontained within said cabinet and including a radio receiver circuit; ahandle; a hinge pivotally securing one end of said handle atop saidcabinet to permit displacement of said handle from a first position inwhich said handle is substantially parallel to the nadjacent surface ofsaid cabinet to a second position in which said handle is angularlydisposed with respect to said surface of said cabinet; a latch mechanismsupported by said cabinet for releasably locking said handle in saidfirst position; a telescopic radio antenna normally supported entirelywithin said handle when said handle is in `said first position andextensible when said handle is in said second position to an operatingposition in which said antenna is angularly and laterally displaced fromsaid chassis to render said antenna free from capacitive loading by saidchassis; and means for electrically connecting said antenna to saidradio receiver circuit.

2. A portable radio receiver comprising: a metal cabinet; a conductivechassis contained within said cabinet and including a radio receivercircuit; a handle; a hinge pivotally securing one end of said handleatop said cabinet to permit displacement of said handle from a firstposition in which said handle is substantially parallel to the adjacentsurface of said cabinet to a second position in which said handle isangularly disposed with respect to said surface of said cabinet and saidconductive chassis; a latch mechanism supported by said cabinet forreleasably locking said handle in said first position; a telescopicradio antenna normally supported entirely within said handle when saidhandle is in said first position and extensible when said handle is insaid second position to an operating position in which said antenna isangularly and later-ally displaced from said metal cabinet and from saidchassis to render said antenna free from capacitive loading by saidchassis or said cabinet; and means for electrically connecting saidantenna to said radio receiver circuit.

References Cited in the le of this patent UNITED STATES PATENTS

